Grafted Motor Nerves Found Effective
A Johns Hopkins animal study suggests that grafted motor nerves may be more effective than sensory nerves for restoring movement. The findings eventually may lead to improved treatment for facial nerve injuries and other nerve peripheral damage in people.
Sensory nerves relay information from the senses to the brain, while motor nerves carry the brain's signals back to the muscles.
Scientists compared the regrowth of bundles of motor nerve fibers in both sensory and motor nerve grafts in rats. They removed sections of both types of nerves from the rats' spines and grafted them into large gaps in a large motor nerve in their legs. Three months later, the results showed that many more of the motor nerve fibers had regenerated.
"Our results suggest that surgeons re-evaluate their traditional use of sensory nerves for grafts in motor, sensory and mixed nerves," says Kyle D. Bickel, M.D., lead author and an assistant professor of plastic surgery and orthopedic surgery.
Grafts using sensory nerves may create numbness in the donor area, while grafts using motor nerves may weaken or paralyze the donor area. Although surgeons usually use sensory nerves because numbness is considered a more acceptable risk, that often means poor function where the graft is placed, says Bickel.
"But if it makes more sense to use motor nerves to restore function, then we may have to reconsider our approach and look for places in the body where a slight loss of muscle movement is acceptable," says Bickel. The study recently was presented at the American Society for Surgery of the Hand's annual meeting.
For media inquiries only, contact John Cramer at (410) 955-1534 or jcramer@welchlink.welch.jhu.edu.
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